Abstract:

I recorded acoustic and visual components of Indian Peafowl (Pavo cristatus) mating displays at the Assiniboine Park Zoo, in Winnipeg, Manitoba, Canada. I determined that males produce infrasound (<20 Hz) in their train displays, and documented responses of peafowl to playbacks of both audible and infrasonic components of their vocalizations and train displays. Peafowl responded to infrasonic signals by increasing alertness and locomotory behaviours, while males also responded by calling. In response to audible call playbacks, males called and faced the playback unit while females increased locomotion and alertness, though peafowl did not respond to audible signal components from the train display, suggesting that infrasonic components constitute the essential signal component within those displays. Beyond revealing a critical role of acoustic signals in modulating interactions among peafowl, my results provide the first empirical evidence of a bird producing and perceiving infrasound as a signal.